Let $x = \frac{a^2 b^2}{c}$ be a physical quantity. If the percentage errors in the measurement of physical quantities $a, b,$ and $c$ are $2\%, 3\%,$ and $4\%$ respectively,then the percentage error in the measurement of $x$ is: (in $\%$)

The most accurate reading of the length of a $6.28 \,cm$ long fibre is ............... $cm$.

If $P = \frac{A^3}{B^{5/2}}$ and $\Delta A$ is the absolute error in $A$ and $\Delta B$ is the absolute error in $B$,then the absolute error $\Delta P$ in $P$ is:

$A$ body travels uniformly a distance of $(13.8 \pm 0.2) \ m$ in a time $(4.0 \pm 0.3) \ s$. The percentage error in velocity is ......... $\%$

Using the expression $2 d \sin \theta = \lambda$,one calculates the values of $d$ by measuring the corresponding angles $\theta$ in the range $0^{\circ}$ to $90^{\circ}$. The wavelength $\lambda$ is exactly known and the error in $\theta$ is constant for all values of $\theta$. As $\theta$ increases from $0^{\circ}$:

State the rule for the error in the result due to multiplication and division of two physical quantities.